What is the treatment for polymyalgia rheumatica (PMR)?

Treatment of Polymyalgia Rheumatica

The first-line treatment for polymyalgia rheumatica (PMR) is oral prednisone at a dose of 12.5-25 mg/day with subsequent individualized tapering over 1-2 years. 1

Initial Glucocorticoid Therapy

• Starting dose recommendations:

  • 12.5-25 mg/day of oral prednisone equivalent 2, 1
  • Doses ≤7.5 mg/day are discouraged due to insufficient efficacy 1
  • Doses >30 mg/day are strongly discouraged due to increased risk of adverse effects without additional benefit 1

• Administration considerations:

  • Single daily doses are preferred over divided doses 1
  • Intramuscular methylprednisolone may be considered in specific cases where lower cumulative glucocorticoid dose is desirable (e.g., female patients with difficult-to-control hypertension, diabetes, osteoporosis, or glaucoma) 2
  • However, evidence for reduced side effects with intramuscular administration is limited 2

Glucocorticoid Tapering Protocol

1. Initial taper:

   • Reduce to 10 mg/day within 4-8 weeks of starting treatment 1

2. Maintenance taper:

   • Once remission is achieved, taper prednisone by 1 mg every 4 weeks (or use alternate day schedules) 1
   • Slow tapering (<1 mg/month) is associated with fewer relapses and more frequent treatment cessation 3
   • Total tapering duration should be at least 1-2 years 1

3. Relapse management:

   • If relapse occurs, increase prednisone to the pre-relapse dose
   • Then gradually decrease (within 4-8 weeks) to the dose at which relapse occurred 1

Methotrexate as a Steroid-Sparing Agent

• Consider methotrexate in patients:

  • At high risk for glucocorticoid-related side effects 2, 1
  • With frequent relapses or requiring prolonged therapy 2, 1
  • Methotrexate has demonstrated effectiveness at doses of 10 mg/week or higher 1, 3

• Methotrexate administration guidelines:

  • Supplement with folic acid (at least 5 mg per week) to reduce toxicity 1
  • Perform baseline assessment including liver function tests, albumin, complete blood count, and creatinine 1
  • Monitor laboratory parameters every 1-1.5 months until stable dose, then every 1-3 months 1
  • Contraindicated in pregnancy planning, pregnancy, and breastfeeding 1

Emerging Therapies

• Anti-IL-6 receptor agents (tocilizumab, sarilumab) have shown efficacy in reducing relapse frequency, lowering glucocorticoid burden, and achieving long-term remission 4
• Anti-TNF agents have not shown benefit in PMR and are strongly discouraged 1, 4

Patient Stratification and Monitoring

• PMR is heterogeneous with variations in treatment duration and corticosteroid requirements 5
• Patients with lower initial ESR may require shorter treatment duration with fewer relapses 5
• Monitor for:
  • Disease activity (symptoms, inflammatory markers)
  • Glucocorticoid-related adverse effects
  • Signs of adrenal insufficiency during tapering 1

Important Caveats and Pitfalls

1. Beware of inadequate initial dosing: Starting with doses below 12.5 mg/day is associated with higher relapse rates. Studies show 65% of patients relapsed on an initial dose of 10 mg/day 6.

2. Avoid overly rapid tapering: Fast tapering regimens (>1 mg/month) lead to more frequent relapses. Slow, gradual reduction is key to successful treatment 3.

3. Consider PMR-to-GCA progression: Monitor for symptoms of giant cell arteritis (headache, jaw claudication, visual disturbances), as some patients with PMR may develop GCA requiring higher glucocorticoid doses 6.

4. Recognize treatment resistance: Patients with persistently elevated IL-6 levels despite treatment may represent a subset with more difficult-to-treat disease requiring more aggressive therapy 7.

5. Balance benefits and risks: The goal is to use the lowest effective dose of glucocorticoids to control symptoms while minimizing adverse effects, particularly in patients with pre-existing conditions that increase steroid-related risks 1.